Enter the sum of all squared percentages in the distribution and the number of categories into the calculator to determine the IQV.

## IQV Formula

The following formula is used to calculate an index of qualitative variation (IQV).

IQV =[ K ( 100^{2} – SUM (Pct^{2} )) ] / 100^{2} (K-1)

- Where IQV is the index of qualitative variation
- K is the number of categories
- Pct^2 is the sum of all squared percentages in the distriubution

## IQV Definition

IQV, which is short for the index of qualitative variation, is a measure of the variability for nominal variables such as race and ethnicity.

IQV values rand from 0 – 1. IQV is 0 when all cases in the distribution are in one category and IQV is 1 when all cases are distributed evenly in each category.

## Example Problem

How to calculate IQV?

**First, determine the total number of categories.**For this example, there are 20 total categories.

**Next, determine the sum of all squared percentages in the distribution.**The sum of the percentages for this example is found to be 7525.

**Finally, calculate the index of qualitative variation.**Using the formula above, the IQV is calculated to be:

IQV =[ K ( 100^{2}– SUM (Pct^{2})) ] / 100^{2}(K-1)

IQV =[ 20 *( 100^^{2}– 7525) ] / (100^^{2}* (20-1) )

IQV = .260